Portion of a shoe sole



FIG. 1 is a right side elevational view of a portion of a shoe sole showing our new design;

FIG. 2 is a front elevational view thereof; and,

FIG. 3 is a rear elevational view thereof.

The broken line showing of the remainder of the shoe in the Figures is environmental and forms no part of the claimed design. 

The ornamental design for a portion of a shoe sole, as shown and described. 